Ellipse-compasses.



PATENTED APR. 10, 1906.

C. B. KEEL. ELLIPSE COMPASSES. APPLICATION FILED JUNE 19. 1905.

2 SHEETSSHEET 1.

PATENTED APR. 10, 1906.

0. E. KBEL. ELLIPSE COMPASS ES.

APPLIOATION FILED JUNE 19. 1905.

2 SHEETSSHEET 2.

UNITED s'rArEs Parana ornioii.

CHARLES E. OF INIEBTAPOLIS, INDIANA.

' suwsswommssas.

Specification of Letters Patent.

Patented April 10, 1906..

Application filed June 19,1905. SerialNo. 266,873.

This invention relates to drawing instruments, and has reference particularly to coml passes for drawin elliptical figures as well as for drawing circ es. r

An object of the invention is to provide an elliptic compass which may be uickly adjusted so that an ellipse of any size and proportion may be drawn accurately.

Another object is to provide an elli tic compass which maybe quickly adjuste so as to be used for drawing circles with the same advantages as with a beam-compass within the range of capacity of the instrument.

The invention consists in an ellipse-comass com rising a pair of legs that are paraliial and ariiustable one to the other, one being the centering-leg and the other one the drawing-leg, a swivel-head on the centering-leg having an adjustable guide pivoted thereto, a beam pivoted to the centering-leg and controlling the positions of the drawing-leg with respect to the centering-leg, and a guidearm and connection controlling the beam.

The invention consists, further, in the novel parts and in the combinations and arrangements of parts, as hereinafter particularly described and claimed.

Referring to the drawings, Figure 1 represents a front elevation of the instrument constructed substantially in accordance with the invention; Fig. 2, a rear elevation thereof; Fig. 3, a side elevation thereof; Fig. 4, a side elevation of the guide-arm Fig. 5, a perspective view of the guide; Fig. 6, a front elevation of the swivel-head; Fig. 7, a vertical central sectional view of the swivel-head and upper portions of the centering-leg, showing the pivoting of the guide and the guide-arm Fig. 8, a side elevation of the swivel-head; Fig. 9, a fragmentary front elevation showing :portions of the drawing-leg and the beam ig. 10, an elevation of the upper portion of the centering-leg; Fig. 11, a sectional detail view showing the connections between the drawing-leg and the beam; Fig. 12, an end view of the guide-bolt for connectin the drawing-leg and the beam together a justably and inovably; Fig. 13, a rear elevation of the instrument, slightly modified in details; Fig. 14, a sectional detail view of the guide having modified securing devices; Fig. 15, a

front elevation of the drawin -leg included in Fig. 13, and Fig. 16 an end view of the drawing-leg shown in Fig. 13.

Similar reference characters in the several figures of the drawings designate corresponding elements or features.

In the drawings, A designates the centering-leg, which is provided with either a crowfoot point a or a needle-point a, as may be desired, at one end thereof, the op osite or upper end 5 of the leg having a s 111 1e 0 and a so a slot (1 anda pivot c, exten ing through the slot. A guide-arm B, having a pivothole f, is thereby mounted on the pivot e, extendin through the slot (1. The guide-arm has a ger g and also two contact-blades h and h. A cap-screw & is inserted in the end of the spindle The swivel-head C comprises a bored body mounted rotatively on the s indle c and having at one end thereof a han e and at its opposite end a pair of jaw-blades 7c and 7c, each having a pivot-hole 17 therein. A sector 12, having a 11p p, is attached to the body of the head, the sector having also a screw-hole 18 therein to receive a binding-screw.

The guide D com rises a circular plate having an aperture therein and provided with a sector m, a pair of ivots n and n being attached to the body of the guide, so as to extend into the aperture Z, which receives the blades 7c and k, the pivots entering the pivotholes in the blades, whereby the guide is pivoted to the head, the sector m engaging the lip p of the sector p, which supports a binding-screw E, that binds the sector m against the lip after adjustments of the guide. The under side of the guide touches the blades h and h of the guide-arm B and is held yieldingly thereto by an elastic washer g between the top of the handle 9' and the head of the screw i. It will be clear from the foregoing that the guide B may be set either at right angles or at various oblique angles to the axis of the swivel-head.

The drawing-leg F has a main guide-bar G and two secondary guide-bars H and H secured thereto, all in parallel arrangement, ex-

tending laterally from the leg, the main guidebar being between the other two guide-bars and supported and guided by rollers I and I as a pair and I and I as another pair mounted on the leg A, the secondary guide-bars being 'uided b bearings r and r, attached to the leg A, al of the guide-bars being closely fitted, so as to move lon itudinally in their guides and serve to keep the leg F parallel to the leg A while being moved to or from it in operation.

A beam J is connected by a ivot s to the leg A and extends across the leg and preferably has finger-holds or handles t at its ends, and a connecting-rod u is iv'oted to the finger g of the guide-arm and also to the beam, so as to hold the beam parallel to the guidearm. The beam is provided with a gradulated scale '0, extendin along the upper side thereof,for measuring t e spread of the le s.

The leg F has a guideway w eXtenrIing lengthwise thereof, and the lower end of the leg is provided with a pencil 19., held by a binding-screw 20, and the leg and bindingscrew may be modified so as to be adapted to carry a stylographic pen in lieu of the encil, as is obvious. A guide-bolt Khas a T- ead y movable in the guideway w, and the bolt also has a flan e 21, that bears against the leg F, the flan e avin a rojection 22, that is bent into a sit as in the eam J for reventing the bolts turning when loose. l washer L is placed on the bolt against the beam and has a projection 23 extending into the slot :0 to prevent rotation of the washer, which is provided with a pointer 24, extending to the scale 12 of the beam. A bindingmut M is placed on the screw K for binding the screw to the beam J, the nut bearing directly against the washer L, the T-head of the bolt at all times being free to move in the guideway w of the leg F upwardly and downwardly while in operation.

In some cases the le F may be formed of two parallel bars suitably connected together, and in other cases the drawing-leg may be composed of sheet metal bent over, as the leg F, Figs. 13, 15, and 16,'to form theguidewayw.

When preferred, the lip 10 may be omitted from the sector The guide D may be provided with an arm N instead of the sector m to cooperate with the sector 1), the arm carrying a binding-screw 0, having a hook 25 and a washer 26, and a binding-nut P on the screw 0, the hook being adapted to engage the sector p to secure the arm N thereto, and thus fix the guide D after adjustment. Either the sector m or the sector p, or each one of them, may be provided with a graduated scale, as is obvious. I

In lieu of the devices above described for maintaining the le s A andF or F in parallel arrangement paral e1 bars S and S and T and T maybe employed. in pairs, onepair S and S being pivoted together and to a connectingsmelt bar U and the other pair T and T being piv-' oted together and also to the bar U, the bars S and T pivoted to the leg A and the bars S and T ivoted to theleg F, (or to the legF,) preferab y by means of projections 27 and 28, attached to the leg and extendin laterally therefrom. Also with the paralle bars may be employed guide-bars Q and Q, secured to the leg A and extending behind guides R and It, that are attached to the drawing-leg F, (or F.)

In practical use, the instrument being held up'rightly, the bindin screw E or the nut P may be oos'ened so t at the guide D may be free to move on its pivots. Then the beam J may be laced in the horizontal position, after whic the binding-nut M ma be loosened, so that the drawing-leg may e adjusted according to the scale 2) to suit the diameter on the major axis of the ellipse that is to be described, after which the nut M should be tightened. Then the guide D should be adjusted at a suitable angle, so as to move the beam J, and thereby draw the drawing-leg toward the legAthe necessar distance to describe the minor diameter 0 the ellipse that may have been predetermined. Then the guide D should be fixed. Then an ellipse may be drawn if the handle 9' of the swivel-head be held in one hand against rotation, while with the other hand the operator moves the drawing-leg about the other or centeringleg, which will be accomplished by reason of the contact-blades of the guide-arm B following the plane of the guide D and through the various connections moving the drawingleg toward and from the centering-leg as the beam J rises and falls from the horizontal.

Having thus described the invention, what is claimed as new is 1. An ellipse-compass including a centerin leg, a drawing-leg carried by and movabIe toward or away from the centering-leg, a head swiveled on the centering-leg and pro videdwith an adjustable uide, a guide-arm pivoted to the centeringeg and controlled by the guide, a beam pivoted to the centering-leg and controlling the movements of the drawing-leg, and a connecting-rod pivoted to the guide-arm and also to the beam.

2. An ellipse-compass including a centering-leg having a head swiveled thereon, a guide mounted on the head and ad ustable angularly with respect to the axis of the leg, a binding-screw for the uide, a guide-arm pivoted to the centerin eg in contact wlth the guide to be actuate thereby, a drawin leg carried by the centering-leg and movab c with respect thereto, a beam pivoted to the centering-leg controlling the movements of the drawing-leg and provided with a graduated scale, and a connecting-rod pivoted to the guide-arm and also to the beam.

3. An ellipse-compass including a centering-leg having a beam pivoted thereto, a

drawing-leg carried by the centering-leg and movable with respect thereto, guides for the drawing-leg, a connecting-bolt secured adjustably-to the beam and having movable connection with the drawing-leg longitudinally thereof, a head swiveled on the centering-leg and supporting a guide adjustably, and a guide-arm pivoted to the centerin -leg and controlled by the guide and controlling the movements of the beam:

4. An ellipse-compass including a centering-leg having a slot therein, a guide-arm in the slot pivoted to the leg, a beam pivoted to the centering-leg, a connecting-rod pivoted tothe guide-arm and also to the beam and maintaining the beam parallel to the guidearm, a drawing-leg carried by the centering leg and movable with respect thereto, a connection between the beam and the drawingleg and controlling the movements of the leg,

and a head swiveled to the centering-1e and having a plane-faced guide adjustab y attached thereto in contact with the guide-arm and thereby controlling the movements of}, the beam and the drawing-leg when the head is held stationary and the centering-leg is rotated relatively thereto.

In testimony whereof I aflix my signature in presence of two witnesses.

CHARLES E. 

